With the wide use of electronic devices such as mobile phones and tablet computers and volume of electronic devices being getting smaller and smaller, there is a growing demand for loudspeakers to be used in the electronic devices. Since a mounting space left for the loudspeaker becomes smaller but the requirements for sound quality increase constantly, the loudspeaker is required to have characteristics such as a small size, a large sound volume, a low distortion, a large power, and the capability of operating in a case of large vibration amplitude.
In the conventional loudspeakers, generally, a top dome is assembled on a vibration diaphragm to form a vibration means. The vibration means is driven by a voice coil to move reciprocally for vibrating and further producing sound. The vibration diaphragm is generally composed of multi-layered films plus adhesive layers, and the material used for the films is generally a polyetheretherketone film material, polyarylate film material or polyurethane film material. Since multiple films are required to be composited and based on the nature of the material itself, the thickness of the vibration diaphragm is small, and then the vibration diaphragm made of multi-layered thin composite materials has a small elastic linear range in vibration, which is apt to produce unbalanced vibration, has a low reliability, and vibrates beyond a linear stretching range when vibrating at a large amplitude, resulting in a high distortion, and further adversely affecting the quality of audio output. Therefore, the conventional loudspeakers cannot be applied to the audio output that requires a high power and a large sound volume.
Accordingly, a technical issue to be addressed currently by the person skilled in the art is to provide a loudspeaker capable of producing high power and large sound volume audio output with low distortion.